<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <script src="https://cdn.jsdelivr.net/npm/vue@2.7.14/dist/vue.js"></script>
</head>
<body>
  <div id="app">
    <button @click="add">生成</button>
    <ul>
      <li v-for="(item, i) in arr" :key="item">
        <span>{{ item }}</span>
        <button @click="del(i)">删除</button>
      </li>
    </ul>
  </div>
  <script>
    const app = new Vue({
      el: '#app',
      data: {
        arr: [1, 5, 3]
      },
      methods: {
        add() {
          this.arr.push(Math.floor(Math.random() * 20));
        },
        del(index) {
          this.arr.splice(index, 1);
        }
      },
    })
  </script>
</body>
</html>